add ppc64le/ppc64 architecture support

Add build and runtime support for ppc64el (little-endian) and ppc64
(big-endian) POWER architectures:

- cmake/DaemonNacl.cmake: add ppc64el/ppc64 case with dummy x86 NaCl
  defines since NaCl has no PPC support
- cmake/DaemonFlags.cmake: add -mcpu=power8 (ppc64el) and -mcpu=power5
  (ppc64) compiler flags using new GCC_GENERIC_CPU variable, as GCC on
  POWER uses -mcpu instead of -march/-mtune
- cmake/DaemonArchitecture.cmake: define ppc64el parent architecture as
  ppc64, and add DAEMON_NACL_RUNTIME_ENABLED compile-time define that is
  only set on architectures with a NaCl loader (amd64, i686, armhf)
- src/engine/framework/VirtualMachine.h: default VM type to native DLL
  mode on architectures without NaCl runtime support, so the engine does
  not attempt to load nonexistent .nexe files

Tested on ppc64le with GCC 16.0.1: builds daemon, daemonded, daemon-tty,
cgame-native-dll.so, and sgame-native-dll.so successfully.

Author: runlevel5

cmake/DaemonArchitecture.cmake

@@ -91,6 +91,12 @@ endif()
 
 daemon_add_buildinfo("char*" "DAEMON_NACL_ARCH_STRING" "\"${NACL_ARCH}\"")
 
+# NaCl runtime is only available on architectures that have a NaCl loader.
+set(NACL_RUNTIME_ARCH amd64 i686 armhf)
+if (NACL_ARCH IN_LIST NACL_RUNTIME_ARCH)
+	add_definitions(-DDAEMON_NACL_RUNTIME_ENABLED=1)
+endif()
+
 option(USE_ARCH_INTRINSICS "Enable custom code using intrinsics functions or asm declarations" ON)
 mark_as_advanced(USE_ARCH_INTRINSICS)
 
@@ -111,6 +117,7 @@ set_arch_intrinsics(${ARCH})
 
 set(amd64_PARENT "i686")
 set(arm64_PARENT "armhf")
+set(ppc64el_PARENT "ppc64")
 
 if (${ARCH}_PARENT)
 	set_arch_intrinsics(${${ARCH}_PARENT})

cmake/DaemonFlags.cmake

@@ -659,6 +659,18 @@ elseif (NOT NACL)
 		set(GCC_GENERIC_ARCH "armv6")
 		# There is no generic tuning option for armv6.
 		unset(GCC_GENERIC_TUNE)
+	elseif (ARCH STREQUAL "ppc64el")
+		# POWER8 minimum (first little-endian POWER).
+		# GCC uses -mcpu instead of -march/-mtune for POWER.
+		unset(GCC_GENERIC_ARCH)
+		unset(GCC_GENERIC_TUNE)
+		set(GCC_GENERIC_CPU "power8")
+	elseif (ARCH STREQUAL "ppc64")
+		# POWER5 minimum (first 64-bit POWER in wide use).
+		# GCC uses -mcpu instead of -march/-mtune for POWER.
+		unset(GCC_GENERIC_ARCH)
+		unset(GCC_GENERIC_TUNE)
+		set(GCC_GENERIC_CPU "power5")
 	else()
 		message(WARNING "Unknown architecture ${ARCH}")
 	endif()
@@ -676,6 +688,11 @@ elseif (NOT NACL)
 		if (GCC_GENERIC_TUNE)
 			try_c_cxx_flag_werror(MTUNE "-mtune=${GCC_GENERIC_TUNE}")
 		endif()
+
+		# POWER architectures use -mcpu instead of -march/-mtune.
+		if (GCC_GENERIC_CPU)
+			try_c_cxx_flag_werror(MCPU "-mcpu=${GCC_GENERIC_CPU}")
+		endif()
 	endif()
 
 	if (USE_CPU_RECOMMENDED_FEATURES)

cmake/DaemonNacl.cmake

@@ -71,6 +71,11 @@ else()
     add_definitions( -DNACL_BUILD_SUBARCH=32 )
   elseif( NACL_ARCH STREQUAL "armhf" )
     add_definitions( -DNACL_BUILD_ARCH=arm )
+  elseif( NACL_ARCH STREQUAL "ppc64el" OR NACL_ARCH STREQUAL "ppc64" )
+    # NaCl does not support PPC, but these defines must be set for native
+    # builds. Use dummy x86 values as PNaCl does for arch-independent builds.
+    add_definitions( -DNACL_BUILD_ARCH=x86 )
+    add_definitions( -DNACL_BUILD_SUBARCH=64 )
   else()
     message(WARNING "Unknown architecture ${NACL_ARCH}")
   endif()

src/engine/framework/VirtualMachine.h

@@ -95,8 +95,13 @@ enum vmType_t {
 struct VMParams {
 	VMParams(std::string name, int vmTypeFlags)
 		: logSyscalls("vm." + name + ".logSyscalls", "dump all the syscalls in the " + name + ".syscallLog file", Cvar::NONE, false),
+#ifdef DAEMON_NACL_RUNTIME_ENABLED
 		  vmType("vm." + name + ".type", "how the vm should be loaded for " + name, vmTypeFlags,
 		         Util::ordinal(vmType_t::TYPE_NACL), 0, Util::ordinal(vmType_t::TYPE_END) - 1),
+#else
+		  vmType("vm." + name + ".type", "how the vm should be loaded for " + name, vmTypeFlags,
+		         Util::ordinal(vmType_t::TYPE_NATIVE_DLL), 0, Util::ordinal(vmType_t::TYPE_END) - 1),
+#endif
 		  debug("vm." + name + ".debug", "run a gdbserver on localhost:4014 to debug the VM", Cvar::NONE, false),
 		  debugLoader("vm." + name + ".debugLoader", "make nacl_loader dump information to " + name + "-nacl_loader.log", Cvar::NONE, 1, 0, 5) {
 	}
@@ -111,7 +116,11 @@ struct VMParams {
 class VMBase {
 public:
 	VMBase(std::string name_, int vmTypeCvarFlags)
+#ifdef DAEMON_NACL_RUNTIME_ENABLED
 		: processHandle(Sys::INVALID_HANDLE), name(name_), type(TYPE_NACL), params(name_, vmTypeCvarFlags) {}
+#else
+		: processHandle(Sys::INVALID_HANDLE), name(name_), type(TYPE_NATIVE_DLL), params(name_, vmTypeCvarFlags) {}
+#endif
 
 	// Create the VM for the named module. This will automatically free any existing VM.
 	void Create();